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Date:   Mon, 29 Aug 2022 13:34:52 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Carlos Llamas <cmllamas@google.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        =?ISO-8859-1?Q? "Arve_?= =?ISO-8859-1?Q?Hj=F8nnev=E5g" ?= 
        <arve@android.com>, Todd Kjos <tkjos@android.com>,
        Martijn Coenen <maco@android.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Christian Brauner <brauner@kernel.org>,
        Suren Baghdasaryan <surenb@google.com>,
        Liam Howlett <liam.howlett@oracle.com>,
        kernel-team@android.com,
        syzbot+f7dc54e5be28950ac459@syzkaller.appspotmail.com,
        syzbot+a75ebe0452711c9e56d9@syzkaller.appspotmail.com,
        stable@vger.kernel.org,
        "Liam R . Howlett" <Liam.Howlett@oracle.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/7] binder: fix alloc->vma_vm_mm null-ptr dereference
Message-Id: <20220829133452.cd4d9abe858c940126557c41@linux-foundation.org>
In-Reply-To: <20220829201254.1814484-2-cmllamas@google.com>
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        <20220829201254.1814484-2-cmllamas@google.com>
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On Mon, 29 Aug 2022 20:12:48 +0000 Carlos Llamas <cmllamas@google.com> wrote:

> Syzbot reported a couple issues introduced by commit 44e602b4e52f
> ("binder_alloc: add missing mmap_lock calls when using the VMA"), in
> which we attempt to acquire the mmap_lock when alloc->vma_vm_mm has not
> been initialized yet.
> 
> This can happen if a binder_proc receives a transaction without having
> previously called mmap() to setup the binder_proc->alloc space in [1].
> Also, a similar issue occurs via binder_alloc_print_pages() when we try
> to dump the debugfs binder stats file in [2].

Thanks.  I assume you'll be merging all these into mainline?

> 
> Fixes: 44e602b4e52f ("binder_alloc: add missing mmap_lock calls when using the VMA")
> Reported-by: syzbot+f7dc54e5be28950ac459@syzkaller.appspotmail.com
> Reported-by: syzbot+a75ebe0452711c9e56d9@syzkaller.appspotmail.com
> Cc: <stable@vger.kernel.org> # v5.15+

44e602b4e52f is only present in 6.0-rcX?